Abstract
Introduction
The neurogenic response to hypoglycemia (HG) is well established. In contrast, neuroglycopenic (NG) manifestations are widely variable and have been erroneously attributed to other diagnoses. Compounding diagnostic uncertainty is the incidence of these symptoms in a patient with a psychiatric illness.
Clinical Case
A 51 year old male with hypertension and schizophrenia maintained on amlodipine, risperidone and benztropine was transported to the ER psychiatric unit by law enforcement. He was detained after he was found wandering the streets demonstrating increased verbal and physical aggressiveness. He was known to the unit, with previous admissions for psychosis secondary to schizophrenia. On presentation vitals were solely significant for tachycardia. Physical and mental status examination revealed a disheveled, agitated and combative male who was disoriented to time, person and location. He was actively experiencing visual and auditory hallucinations with psychomotor agitation, intermittent loosening of association, circumstantial speech and persecutory delusions. Initially given one dose of i.m. haloperidol and benztropine, his psychosis persisted. Biochemical investigations were significant for a glucose of 37 mg/dL; All others including alcohol level, toxicology and TSH were normal. Head CT was unremarkable. His HG was treated with i.v. dextrose with complete resolution of psychotic symptoms within one hour of normoglycemia. He needed no further antipsychotic doses save his maintenance risperidone. Further historical enquiry revealed a recent diagnosis of type 2 DM managed on metformin and glimepiride with poor oral intake. He was discharged on metformin and sitagliptin post extensive DM self-management education, h; glimepiride was discontinued.
Discussion
NG manifestations of hypoglycemia are the direct result of central nervous system glucose deprivation. Uncommonly, they can be the sole presenting complaint in the HG patient. In one study, 27% of patients with insulinomas had only NG symptoms [1]. Interestingly, some case reports suggest acute psychosis may be an important NG feature [2]. Psychiatric patients, particularly those with primary psychotic disorders often face a labyrinthine process when seeking emergent medical care including but not limited to anchoring and ascertainment physician bias. If unrecognized, HG can lead to neuronal death. Clinicians must maintain a high index of suspicion of HG in patients presenting with acute psychosis even in the presence of functional illness so as to reduce morbidity, mortality and medicolegal risk.
References
Dizon AM., Kowalyk S., Hoogwerf BJ. Neuroglycopenic and other symptoms in patients with insulinomas, Am J Med. 1999 Mar; 106(3):307-10.
Klemen P., Grmec S., Cander, D. Hypoglycemia masquerading as acute psychosis in young age. Crit Care. 2000; 4(Suppl 1): P172. doi: 10.1186/cc892.
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